The present invention relates to fluoromonomers. It also relates to processes for the copolymerization of fluoromonomers with fluoroolefins, to the resulting copolymers and to the use of these monomers in forming in particular fluoroelastomers. In addition, the present invention relates to a process for the crosslinking of these copolymers.
A large number of fluoromonomers have already been disclosed in the literature.
The synthesis of fluoroolefins corresponding to the general formula CF2xe2x95x90CF(CF2)m(CH2)nOH (with m=0 to 10 and n=1 to 4) is disclosed in Patent Application EP 0 138 091. The use of fluoroolefins as comonomers of vinylidene fluoride is also envisaged.
Patent Application EP 0 135 917 discloses fluorocopoymers formed by copolymerization of vinylidene fluoride with fluoroolefins of general formula CF2xe2x95x90CF(CF2)m(CH2)nX (with X=OH, COOH or an epoxide group, m=0 to 10 and n=1 to 4). The copolymerization of some of these compounds with vinylidene fluoride is described therein.
Patent U.S. Pat. No. 3,483,263 discloses the synthesis of unsaturated haloalcohols corresponding to the formula CX1X2xe2x95x90CX3xe2x80x94Axe2x80x94OH in which X1 to X3 represent halogen atoms and A represents an alkylene group comprising at least two carbon atoms.
T. Nguyen et al., in J. Organic. Chem., 54(23), 5640-5642, 1989, disclose the synthesis of a compound corresponding to the formula CF2xe2x95x90CFCH2OH by addition of methyllithium to 2,2,3,3-tetrafluoropropanol.
The document SU 375298 discloses the use of CF2xe2x95x90CFCH2OH in the preparation of O-(2,3,3-trifluoroalkyl) phosphonates.
The document WO 86/07590 relates to pesticides corresponding to the general formula CF2xe2x95x90CFxe2x80x94(CH2)nxe2x80x94Xxe2x80x94R in which X can be O, N, S or CH2 and n can have the values from 1 to 4, the value of R depending on the meaning of X.
The use of compounds of formula CF2xe2x95x90CFxe2x80x94CH2Q as pesticides is revealed in United States of America Patent U.S. Pat. No. 5,514,717.
W. R. Dolbier et al., in J. Chem. Soc. Perkin Trans., 2, 219-232, 1998, analysed the cyclization activities of hex-5-enyl radicals and disclosed, inter alia, the synthesis of the compound 4,5,5-trifluoropent-4-enol.
T. Dubuffet et al., in J. Organomet. Chem., 341, 11-18, 1998, reveal a process for the opening of oxetanes under the action of fluorinated organolithium derivatives. Test 13 gives access to the compound 4,5,5-trifluoropent-4-enol.
An object of the present invention consists in making available novel fluoromonomers.
This object is achieved by compounds corresponding to the formula I
CF2xe2x95x90CFxe2x80x94(CH2)mxe2x80x94Wxe2x80x83xe2x80x83(I)
in which
m has the value 1, 2 or 3,
W represents a CH(OH)CH2OH group, a 
group, 
in which
R1, R2, R3 and R4 independently represent a hydrogen atom, a C1-C20 alkyl group or an optionally substituted aryl group
R5 and R6 independently represent a hydrogen atom, a C1-C20 alkyl group or an optionally substituted aryl group, with the proviso that, when R5 represents a hydrogen atom, R6 is other than a phenyl group when m has the value 1
R7 and R8 independently represent a hydrogen atom, a C1-C20 alkyl group or an optionally substituted aryl group, with the proviso that R7 and R8 do not both represent a hydrogen atom or an ethyl group when m has the value 1
Y represents an oxygen atom or a sulphur atom and
Z represents a hydrogen atom, a CH2CH2OH group, a CH2COOH group or a COCH3 group,
with the proviso that, when W represents CH(OH)CH2OH, m has the value 1, when Y represents an oxygen atom, Z is not a hydrogen atom and, when Y represents S, m has the value 3.
More particularly, the present invention provides compounds corresponding to the formula II
CF2xe2x95x90CFxe2x80x94C3H6xe2x80x94Yxe2x80x94Zxe2x80x83xe2x80x83(II)
in which Y and Z are as defined above.
Another compound according to the present invention corresponds to the formula
CF2xe2x95x90CFxe2x95x90CH2xe2x80x94CH(OH)xe2x80x94CH2OH.
Another object of the present invention is a copolymerization process comprising the reaction of a compound corresponding to the formula Ixe2x80x2
CF2xe2x95x90CFxe2x80x94(CH2)mxe2x80x94Wxe2x80x2xe2x80x83xe2x80x83(Ixe2x80x2)
in which
m has the value 1, 2 or 3,
Wxe2x80x2 represents a CH(OH)CH2OH group, a CHxe2x95x90CH2 group, 
in which
R1, R2, R3, R4, R5, R6, R7 and R8 independently represent a hydrogen atom, a C1-C20 alkyl group or an optionally substituted aryl group
Y represents an oxygen atom or a sulphur atom and
Zxe2x80x2 represents a hydrogen atom, a CH2CH2OH group, a CH2COOH group or a COCH3 group,
with a compound corresponding to the formula III
CF2xe2x95x90CX2xe2x80x83xe2x80x83(III)
in which
X independently represents a hydrogen atom or a fluorine atom
with the proviso that, when m has the value 1 and X represents a hydrogen atom, Wxe2x80x2 does not represent a 
group,
so as to obtain a fluorocopolymer.
One embodiment of the present invention is a copolymerization process comprising the reaction of a compound corresponding to the formula Ixe2x80x2
in which
m has the value 1, 2 or 3,
Wxe2x80x2 represents Yxe2x80x94Zxe2x80x2 and Y represents an oxygen atom and Zxe2x80x2 represents a hydrogen atom
with a compound corresponding to the formula III in which X independently represents a hydrogen atom or a fluorine atom
so as to obtain a copolymer corresponding to the formula IV 
n, p and r independently representing natural integers.
An additional aspect of the present invention is a copolymerization process comprising the reaction of a compound corresponding to the formula Ixe2x80x2
in which
m has the value 1, 2 or 3,
Wxe2x80x2 represents Yxe2x80x94Zxe2x80x2 and Y represents an oxygen atom and Zxe2x80x2 represents a COCH3 group
with a compound corresponding to the formula III in which X independently represents a hydrogen atom or a fluorine atom
so as to obtain a copolymer corresponding to the formula V 
n, p and r independently representing natural integers.
The present invention also envisages a copolymerization process comprising the reaction of a co compound corresponding to the formula Ixe2x80x2
in which
m has the value 1, 2 or 3,
Wxe2x80x2 represents Yxe2x80x94Zxe2x80x2 and Y represents a sulphur atom and Zxe2x80x2 represents a COCH3 group
with a compound corresponding to the formula III in which X independently represents a hydrogen atom or a fluorine atom
so as to obtain a copolymer corresponding to the formula VI 
n, p and r independently representing natural integers.
According to yet another preferred embodiment, a copolymerization process is provided comprising the reaction of a compound corresponding to the formula Ixe2x80x2
CF2xe2x95x90CFxe2x80x94(CH2)mxe2x80x94Wxe2x80x2xe2x80x83xe2x80x83(Ixe2x80x2)
in which
m has the value 1, 2 or 3,
Wxe2x80x2 represents a CH(OH)CH2OH group, a CHxe2x95x90CH2 group, 
in which
R1, R2, R3, R4, R5, R6, R7 and R8 independently represent a hydrogen atom, a C1-C20 alkyl group or an optionally substituted aryl group
Y represents an oxygen atom or a sulphur atom and
Zxe2x80x2 represents a hydrogen atom, a CH2CH2OH group, a CH2COOH group or a COCH3 group,
with a compound corresponding to the formula III
CF2xe2x95x90CX2xe2x80x83xe2x80x83(III)
in which
X independently represents a hydrogen atom or a fluorine atom
and with an olefinic compound
so as to obtain a copolymer.
More particularly, the invention relates to a copolymerization process comprising the reaction of a compound corresponding to the formula Ixe2x80x2
in which
m has the value 1, 2 or 3,
Wxe2x80x2 represents Yxe2x80x94Zxe2x80x2 and Y represents an oxygen atom and Zxe2x80x2 represents a hydrogen atom
with a compound corresponding to the formula III in which X independently represents a hydrogen atom or a fluorine atom
and with an olefinic compound of formula CH2xe2x95x90CHRxe2x80x2 with Rxe2x80x2 representing a hydrogen atom or a C1-C4 alkyl group so as to obtain a copolymer corresponding to the formula VII 
l, n, p and r independently representing natural integers. Examples of C1-C4 alkyl groups are ethylene, propylene and butylene.
Fluoropolymers possess outstanding properties, such as their hydro- and bleophobicity, their thermal stability, their chemical inertia to acids, to bases, to solvents and to hydrocarbons, their resistance to ageing and to UV radiation and their low surface tension. They find highly varied applications, often in high-tech industries, such as microelectronics, the chemical industry, the automobile industry, the petroleum industry and the aeronautics industry. However, the high melting and glass transition temperatures of most of these polymers prove to be a limitation on their use which thus requires a significant energy input.
In order to limit this disadvantage, the present invention provides, according to another of its aspects, copolymers corresponding to the general formula VIII 
in which
m has the value 1, 2 or 3,
X independently represents a hydrogen atom or a fluorine atom,
n, p and r independently represent natural integers, and
Wxe2x80x2 represents a CH(OH)CH2OH group, a CHxe2x95x90CH2 group, 
in which
R1, R2, R3, R4, R5, R6, R7 and R8 independently represent a hydrogen atom, a C1-C20 alkyl group or an optionally substituted aryl group
Y represents an oxygen atom or a sulphur atom and
Zxe2x80x2 represents a hydrogen atom, a CH2CH2OH group, a CH2COOH group or a COCH3 group.
More specifically, the present invention relates to copolymers corresponding to the formula IV 
in which
m has the value 1, 2 or 3,
X independently represents a hydrogen atom or a fluorine atom and
n, p and r independently represent natural integers.
The present invention also relates to copolymers corresponding to the formula V 
in which
m has the value 1, 2 or 3,
X independently represents a hydrogen atom or a fluorine atom and
n, p and r independently represent natural integers.
The present invention also relates to copolymers corresponding to the formula VI 
in which
m has the value 1, 2 or 3,
X independently represents a hydrogen atom or a fluorine atom and
n, p and r independently represent natural integers.
Other copolymers provided by the present invention are copolymers corresponding to the general formula IX 
in which
m has the value 1, 2 or 3,
X independently represents a hydrogen atom or a fluorine atom,
l, n, p and r independently represent natural integers,
Rxe2x80x2 represents a hydrogen atom or a C1-C4 alkyl group and
Wxe2x80x2 represents a CH(OH)CH2OH group, a CHxe2x95x90CH2 group, 
in which
R1, R2, R3, R4, R5, R6, R7 and R8 independently represent a hydrogen atom, a C1-C20 alkyl group or an optionally substituted aryl group
Y represents an oxygen atom or a sulphur atom and
Zxe2x80x2 represents a hydrogen atom, a CH2CH2OH group, a CH2COOH group or a COCH3 group.
More specifically, the present invention provides copolymers corresponding to the formula IX,
in which
m has the value 1, 2 or 3,
X independently represents a hydrogen atom or a fluorine atom,
Wxe2x80x2 represents Yxe2x80x94Zxe2x80x2 and Y represents an oxygen atom and Zxe2x80x2 represents a hydrogen atom
l, n, p and r independently represent natural integers and Rxe2x80x2 represents a hydrogen atom or a C1-C4 alkyl group.
These copolymers comprise monomers exhibiting the CF2xe2x95x90CFxe2x80x94Rxe2x80x3xe2x80x94Wxe2x80x2 structure, Rxe2x80x3 denoting a spacer arm of variable length targeted at introducing free volumes and at thus reducing the melting and glass transition temperatures.
In order to further improve the properties (particularly mechanical properties) of these fluoro(co)polymers, it is often desirable to crosslink them but this crosslinking to date has required the use of nucleophilic agents (such as diamines or bisphenols) or of radical systems (triallyl cyanurate radicals) or electron bombardment. Consequently, with the aim of avoiding this additional stage, which constitutes a fairly complex procedure, the present invention provides for the incorporation of crosslinking sites (Wxe2x80x2 functional group in the above fluoromonomers) directly in the (co)polymers.
An additional object of the present invention is a crosslinking process comprising the stages of
a) optional deprotection of the functional groups of copolymers obtained above,
b) reaction of the resulting copolymers with an unconjugated C5-C8 diene,
so as to obtain crosslinked copolymers.
Examples of unconjugated dienes are 1,4-pentadiene, 1,5-hexadiene, 1,7-octadiene and 1,9-decadiene. The use of 1,5-hexadiene as unconjugated diene is particularly preferred.
Finally, the use is also provided of compounds corresponding to the formula Ixe2x80x2
CF2xe2x95x90CFxe2x80x94(CH2)mWxe2x80x2xe2x80x83xe2x80x83(Ixe2x80x2)
in which
m has the value 1, 2 or 3,
Wxe2x80x2 represents a CH(OH)CH2OH group, a CHxe2x95x90CH2 group, 
in which
R1, R2, R3, R4, R5, R6, R7 and R8 independently represent a hydrogen atom, a C1-C20 alkyl group or an optionally substituted aryl group
Y represents an oxygen atom or a sulphur atom and
Zxe2x80x2 represents a hydrogen atom, a CH2CH2OH group, a CH2COOH group or a COCH3 group,
with a compound corresponding to the formula III
xe2x80x83CF2xe2x95x90CX2xe2x80x83xe2x80x83(III)
in which X independently represents a hydrogen atom or a fluorine atom, preferably a hydrogen atom and optionally with an olefinic compound, to form fluoroelastomers. Examples of olefinic compounds are ethylene, propylene and butylene. The olefinic compound is preferably propylene.